Vessel lining method



April 4, 1967 H. E. HICKS ETAL 3,311,971

VESSEL LINING METHOD Filed Jan. 16, 1964 5 Sheets-Sheet l INVENTORS. Y#42412 46. H/GkS BY C/lfl/FLES All/B85451? Myw M April 4, 1967 H. E.HICKS ETAL 3,311,971

April 4, 1967 E. HICKS ETAL VESSEL LINING METHOD Filed Jan. 16, 1964 5Sheets-Sheet 3 INVENTORS. H/MML] 4e. Ana/ 5 BY 67/0/9165 (Ml/881E258 WjwMW #770 lam-ya, v

April 4, 1967 H. E. HICKS ETAL 3,

VESSEL LINING METHOD Filed Jan. 16, 1964 5 Sheets-Sheet 5 I I P AINVENTORJ. HFIFWLD E HICKS BY 'flflPAE- 46 223545? United States Patent3,311,971 VESSEL LHNING METHQD Harold E. HiCliS, Kiriswood, and CharlesL. Hihheler, Lemay, Mm, assignors to Nooter Corporation, St. Louis, Mo.,a corporation of Missouri Filed Jan. 16, 1964, Ser. No. 338,128 3Claims. (Cl. 29-523) The present invention relates to a method of liningvessels. The present invention also relates to a method of makingmultiwall pressure vessels.

One of the problems in lining vessels or large tanks as well as inmaking multi-wall pressure vessels is achieving intimate contact betweenthe tank inner wall and the corrosion resistant lining throughout thesurface area of the tank. The present invention achieves this byexpanding a continuous corrosion resistant liner (stainless steel,zircalloy, zirconium or titanium, etc.) by means of a rotatingpressurized roller which expands the liner into intimate contact withthe inner surface of the vessel. In achieving this structure, a vesselwhich might be 30 feet long, 2 feet in diameter, and several inchesthick is provided with a liner which may be up to /2 inch thick andwhich is of slightly less outside diameter than the inside diameter ofthe vessel. The liner is slipped into the vessel, the mechanism isplaced within the liner, hydraulic pressure of the desired force isapplied to the rollers, and the mechanism is rolled through the vesselto force the liner outwardly into intimate contact with the innersurface of the tank. The ends of the liner then may be anchored inplace, and additional rolling of the liner will pre-stress the liner ina longitudinal direction as well as in a circumferential direction.

One of the principal objects of the present invention is to provide amethod of applying a liner to a vessel whereby the liner is in intimatecontact with the inner surface of the vessel to which it is applied.Another principal object of the present invention is to provide a methodof making a multi-wall vessel wherein the liner layers are givendifferent degrees of pre-stress which may be in the longitudinal as wellas the circumferential direction.

Another object is to provide a method of using a rotatable roller devicewhich may be aligned with the helical angle of rotation to prevent endthrust on the feed screw and to eliminate wear on the thrust washersholding the roller in position.

These and other objects and advantages will become apparent hereinafter.

The present invention comprises a method of applying a liner to theinside of a vessel by expanding the liner outwardly into intimatecontact with the vessel.

In the drawings wherein like numbers refer to like parts wherever theyoccur:

FIG. 1 is a sectional view showing the present invention applied to anopen ended vessel,

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1,

FIG. 3 is a sectional view taken along line 3-3 of FIG. 1,

FIG. 4 is an enlarged view in plan of the roller mechanism,

FIG. 5 is a sectional view taken along line 5-5 of FIG. 4,

FIG. 6 is an enlarged fragmentary view showing the roller and rolleractuating screw,

FIG. 7 is a sectional view taken along line 7-7 of FIG. 6,

FIG. 8 is a fragmentary elevational view taken along line 8-3 of FIG. 1,

FIG. 9 is a sectional view partly in elevation showing the presentinvention applied to a closed end vessel,

partly in section and partly ice FIG. 10 is an enlarged sectional viewshowing a spider adjusting means shown in FIG. 9,

FIG. 11 is a sectional view taken along line 1111 of FIG. 10,

FIGS. 12-14 are enlarged fragmentary views partly in section and partlyin elevation showing the adjustment of the roller so that the axis ofthe roller is lined up with the helix curve of the path of rolling,

FIG. 15 is a fragmentary tforeshortened view showing a structure forretaining a liner in a shell, and

FIG. 16 is a fragmentary sectional view showing a method of retaining aliner in a shell when the liner cannot be welded directly to the shell.

The present invention comprises a liner applying machine 10 whichconsists of a olid cylindrical bar 11 mounted in bearings 12 and 13 atthe opposed ends thereof. A drive means 14 rotates the bar 11 through aworm drive gear mechanism 15 positioned in a housing 15a which alsohouses the bearings 13. A centering spider 16 carries the front bearing12 and is adjustable to center the bar 11 in the vessel 17. As shownmore clearly in FIG. 3, the centering spider 16 includes legs 16a .heldin position against the inner surface of the vessel 17 by lock nuts 16b.

A liner applying roller mechanism 18 is rotatably mounted on the bar 11and comprises a housing 19, and three spaced cylinders 20 connected inseries with an accumulator 21 (FIG. 2) by conduits 22, and connected toan outside source of hydraulic fluid H by a conduit 22a. Rotatablerollers 23 are mounted on axles 24 carried by pistons 25 mounted in thecylinders 20. The back side of each piston 25 is connected to anexpansi'ble chamber 26 which is connected to the source of hydraulicfluid H through the conduits 22 and 22a. A half-nut 27 is mounted bysuitable means 28 on the housing 19 which supports the cylinders 20, andis threaded on its inner surface to engage a feed screw 29 mounted alongthe surface of the bar 11 (FIG. 6). A gear 2% is fastened to the end ofthe :feed screw 29 and is meshed with a gear 29a which is connected to ahandle 30 which engages a stop 31 mounted on the "base plate of thedevice. Therefore, when the bar 11 is rotated, the fixed gear 29arotates the gear 2% and the screw 29 with respect to the bar 11. Sincethe housing 19. is keyed to the bar 11, and therefore movable only in alongitudinal direction with respect to the bar 11, the rotation of thebar 11 also rotates the housing 19, and the rotation of the screw 29drives the housing 19 along the outside of the bar 11.

In applying a lining to a vessel, the lining 32 is constructed to havean outside diameter slightly smaller than the inside diameter of thevessel, i.e., approximately 4;" diameter difference, and positionedwithin the vessel. The bar 11 is fixed in the vessel 17 by adjusting thespider retainer 16, the outside source of hydraulic power H is connectedto the fluid lines 22 and 22a, and hydraulic power is applied to thepistons 25 through the expansible chamber 26. Normally the mechanism 18is near an open end of the vessel 17 for convenience. The pistons 25 aremoved outwardly into engagement with the inner surface of the liner 32(FIG. 2) and maintained there by the predetermined and suitablehydraulic pressure applied behind the pistons 25 which may be on theorder of 3000 p.s.i. The fluid also passes into the accumulator 21,which is sealed and contains a gas (such as nitrogen). The gas is placedunder pressure by the hydraulic fluid and maintains within close limitsthe proper hydraulic pressure on the pistons 25 regardless of minorvariations in diameter of vessel and liner, or expansion or leakage ofhydraulic fluid. When the pistons 25 are snfiiciently pressurized, avalve 33 is closed and the fluid pressure source H is disconnected.

A pressure pump could be mounted directly on the mechanism 18 and rotatetherewith, if desired.

The motor 14 is energized and rotates the bar 11 through the drive gear15. The bar 11 rotates the cylinder housing 19 through the keying actionof the half-nut 27. As mentioned, the feed screw 29 and gear 29b areconnected to a second gear 29a at one end. The handle 36} and stop 31prevent rotation of the gear 29a'during rotation of the bar 11, and ineffect rotate the screw 29 with respect to the bar 11 as the screw 29also rotates with the bar 11. Since the half-nut 27 also is threaded tothe screw 29, as the screw 29 is turned by the gear 2%, the half-nut 27(and the entire liner applying mechanism 18) are moved along the bar 11axially. As previously mentioned, the mechanism 18 also rotates with thebar 11, so that the pistons and the roller 23 are rotated around andalong the inner surface of the liner 32. This presses the liner 32outwardly into intimate contact with the inner surface of the vessel 17.

FIGS. 12-14 show a structure for rotating the rollers 23 so that therollers 23 are aligned with the helix angle of the path of rolling toprevent undue wear on the feed screw 29 or the roller thrust washers.Since the rollers 23 are pressing against up to one-half inch wallthickness in the liner 32, there is tremendous side thrust unless therollers 23 are rolling along the path of the helix.

The adjustment mechanism comprises a separated rolle-r housing 34 whichretains the cylinder 20 and the piston 25. Lock bolts 35 are loosened toenable the cylinder 20 to be rotated with respect to the housing 34.When the proper angle of the roller 23 with respect to the housing 34 isobtained, the bolts 35 are tightened to lock the roller 23 in its newangular position.

FIGS. 9-11 show a modification used when the pressure vessel 17a has aclosed end prior to application of the liner 32. In this modification,the gear 29a, handle 30, and stop 31 are positioned adjacent to the endof the vessel 17a at which the drive motor 14 is located.

The principal difference exists in the spider positioning means 36 whichsupports the end of the bar 11 Within the vessel 17a. The spider 36supports a bearing 12 for the bar 11 and is adapted to be positionedwithin the vessel 1711 from the open end of the vessel 17a. The spideris supported by four legs 37 slidably positioned in bore 38 in a spiderhousing 3'9 and adapted to engage the inner surface of the liner 32 orthe vessel 17a. The inner end of each leg 37 is provided with aninclined surface 40 cut at about a angle. Each surface 40 is positionedso as to face the open end of the vessel 17a.

A second bore 41 is formed in the housing 39 at right angles to thefirst bore 33 and facing the open end of the vessel 17a. A portion ofthe bore 41 is threaded at 42. A lock cam 43 having a tapered 45 surface44 is placed in the forward end of the bore 4 1 so that the surface 44mates with the tapered surface 40 on the leg 37. A longitudinal keyway45 is positioned in the outer surface of the cam 43 and a key 46 engagesthe keyway 45 to permit the cam 43 to move only in an axial direction. Ascrew 47 engages the threaded portion of the bore 42 and may be rotatedfrom the open end of the vessel 17a to move the cam 43 into or out ofthe bore 41 and to correspondingly move the leg 37 out of or into thebore 38.

The present invention can be used to pro-stress the liner 32 in acircumferential direction, so that when the vessel 17 later is put underpressure in use, the stress in the liner 32 is as close to zero aspossible, because the corrosion resistance of the liner 32 is best whenit is at zero stress.

It is also possible to pro-stress the liner 32 in a longitudinaldirection by anchoring the ends of the liner 32 by the use of welds 48(FIG. 16). A subsequent rolling of the liner 32 produces longitudinalstretch, since the rolling action tends to lengthen the liner 32 (asmuch as 4-5 inches in a 15 foot liner). With the ends of the liner 32contained by the welds 43, the liner 32 cannot stretch and is thuspre-stresscd. When the liner 32 is rolled onto the inner wall of thevessel 17, it is pro-stressed com- 4 pressively in a circumferentialdirection. Thus in use, under internal pressure, the stresses tend toapproach zero in the liner 32.

If the vessel liner 32 is of a reactive material (such as titanium,zircalloy, etc.) which cannot be welded to steel (which normally is thenature of the vessel 17) an end closure such as shown in FIG. 16 may beused to retain the liner 32 in position. In this arrangement, a groove50 is formed in the end of the vessel 17b and threaded. A liner 3-2 isrolled into position against the inner surface of the vessel 17b. Atitanium end ring 51 is threaded into the vessel 17b and a titanium weld52 is deposited between the end of the liner 32 and the ring 51 to bondthe two together. A subsequent application of the liner apparatus willpre-stress the liner 32 in both the circumferential and longitudinaldirections.

As mentioned, the present invention can be used in making 'multi-wallvessels and would involve the rolling in of a plurality of liners orvessel walls in a manner similar to that hereinbefore described forapplying a single liner to a solid vessel. In accomplishing this, themulti- Wall vessel would have the outer walls pre-stressed in tensionand the inner walls pre-stressed in compression so that when the tank isunder operating pressure, the stress distribution between the inner andouter layers will tend to be of same order of magnitude. As is wellknown, the stress in the inner wall rises considerably faster than thestress in the outer wall as the internal pressure of the vessel isincreased.

This invention is intended to cover all changes and modifications of theexamples of the invention herein chosen for purposes of the disclosure,which do not constitute departures from the spirit and scope of theinvention.

What is claimed is:

1. A method of lining vessels including the steps of positioning a linerin a vessel with clearance between the inner surface of the vessel andthe outer surface of the liner, forcing the liner outwardly intocontacting relation with the vessel inner wall surface, to prestress theliner in a circumferential direction, anchoring the liner with respectto the vessel in a longitudinal direction after forcing the liner intoclose contacting relation with the vessel inner Wall surface, andthereafter applying a force to the liner tending to stress said liner ina longitudinal direction.

2. A method of lining vessels including the steps of positioning a linerin a vessel with clearance between the inner surface of the vessel andthe outer surface of the liner, and applying a constant force in ahelical path circumferentially around the inner surface of the linerfrom one end of the liner to the other to force the liner outwardly intocontacting relation with the inner surface of the vessel, subsequentlyanchoring the liner against longitudinal movement with respect to thevessel, and again applying a constant force in a helical pathcircumferentially around the inner surface of the liner from one end ofthe liner to the other to prestress the liner in both longitudinal andcircumferential directions.

3. A method of applying an internal liner to a cylindrical vessel,including the steps of (a) positioning a cylindrical liner in acylindrical shell 7 with clearance therebetween,

(b) introducing a roller into the liner in spaced relation to the innersurface thereof,

(c) engaging the roller against the liner Wall to urge the Walloutwardly, aligning the roler with the helix angle of the path ofrolling and moving the roller along the inner surface without sidethrust,

(d) moving the roller in a helical path longitudinally along the innerwall surface to expand the liner into conforming contact with thecylindrical vessel,

(e) anchoring the liner against longitudinal movement with respect tothe vessel after the liner has been rolled into engagement with thevessel, and then movingthe roller in a second pass along a helical 5 Epath along the inner surface of the liner to pre- 1,944,380 1/1934Vance. stress the liner in a longitudinal direction. 2,499,630 3/1950Clark 72113 2,575,938 11/1951 Brenneke 29--523 X References Cited by theExaminer 2,600,800 6/ 1952 P t 1 UNITED STATES PATENTS 5 3,156,042 10/1962 Reed- 1472936 10/1923 Anders et CHARLIE T. MOON, Primary Examiner.

1. A METHOD OF LINING VESSELS INCLUDING THE STEPS OF POSITIONING A LINERIN A VESSEL WITH CLEARANCE BETWEEN THE INNER SURFACE OF THE VESSEL ANDTHE OUTER SURFACE OF THE LINER, FORCING THE LINER OUTWARDLY INTOCONTACTING RELATION WITH THE VESSEL INNER WALL SURFACE, TO PRESTRESS THELINER IN A CIRCUMFERENTIAL DIRECTION, ANCHORING THE LINER WITH RESPECTTO THE VESSEL IN A LONGITUDINAL DIRECTION AFTER FORCING THE LINER INTOCLOSE CONTACTING RELATION WITH THE VESSEL INNER WALL SURFACE, ANDTHEREAFTER APPLYING A FORCE TO THE LINER TENDING TO STRESS SAID LINER INA LONGITUDINAL DIRECTION.